e.g. WHILE listening Internet Radio, if
display is closed (i.e. sleep) ... , WHEN turn the display on again, the radio
is still alive, so called "ALIVE" ... ; Because of the radio alive, Gadgets are
also alive; In 3D development, gadgets can be 1 layer WHICH is similar to
background layer; 1st to understand online; 2nd to understand offline; 3rd to
develop both (i.e. offline AND online);

a.k.a. standard IO; to replace punch cards, typing device
WHERE character set can be typed in; font can be typed in;

IFF old style IDE stdio standard i/o keyboard, and then
make sure 3 keys light, they are NumLck, CapLck, and ScrLck
keys;

IFF wireless, in some systems, wireless plug-and-play can
be non-functional at stage 1 step 1, and then start with dual-voltage non-USB
keyboard and mouse 1st for testing IDE/ATA/SATA/SCSI/..., and then test USB bus
from USB keyboard's NumLck key 2nd, after USB is in functional with keyboard's NumLck key and then time to do functional wireless keyboard and mouse 3rd;
remark: between 2nd and 3rd, some systems may have OS installation difficulties
because systems have been evolving from micro-
to nano- ...
;

IFF LFS 2.01, wireless keyboard and wireless mouse can be
at 1 USB; USB keyboard is a new design;